Coal mining method and apparatus



N. D. LEVIN Sept. 1, 1931.

METHOD AND APPARATUS COAL MINING original Filed Mal-oh 2o 1924 5 sheets-sheet 1 Sept.. 1, 1931.

N. D. LEVlN COAL MINING METHOD AND APPARATUS Original Filed March 20', 1924 5 Sheets-Sheet 2 f #few Sepi. l, 1931. Y N. D. LEVIN 1,821,439

COAL MINING METHOD AND APPARATUS Original Filed March 20. 1924 5 Sheets-Sheet 3 lo d fig.

ATme/EYS Sept. l, 1931. N, D, EVlN 1,821,439

COAL MINING METHOD AND APPARATUS original Filed' March 20, 1924 5 sheets-sheet 4 N ,lg f w'poj' A TTo EVS mQM/ Y Sept. 1, 1931. N D, LEV|N 1,821,439

coAL MINING METHOD AND APPARATUS original Filed March 2o, 1924 5 sheets-sheet 5 @Moz nuria Patented Sept. 1, 1931 OFFIeB NILs n. Levin; 'or coLuMBUsjoHm Assienon To THE JEFFREY MANUFACTURING communes coLUMBUsoHio; A conoanfrrcn or omo ooAL Mnvme .ivinrrzaonI 'AND Animar-irs t V'Application fried March' 20,' 1924; serial'v No. 70eme. yRenewedivovembeigs; 1930.

Thepresent invention relates to'oertain new and useful improvements in coal' mining methods and apparatus, andv particularly to a method-f andrk apparatus adapted vto be used along the entire length of an elongatedcoalface to undercut the coal, or to undercut'andv` then transport the dislodged coall longitudinally of the face.

Under some geological conditions coal maybe efficiently recovered fromitsnatural bed by the panel' system of mining, in which parallel entries are iirst driven 'into the-vein, and? the intervening coal isA afterwards re# moved from relatively -long working-faces extending between adjacent entries, the roof beingallowed to subside behind the mining operations. Machines of various sorts, the

active elementsfoff which extend along the' entire length ofY a mine face, have been pro-y vided for undercuttin g the coal and Vfor trans-V porting the dislodged coalE longitudinally of' tliefacetobe loaded into-receptacles suitably? placed in the entries for its" removal from' the mine. i

More particularly is the present develop, ment intended to provide a method and; apparatus of cutting coal, which consists in first kerng out a' coal section,then dislodging thel coal, and preferably, and, as here described, removing'it by the same instrumen` talities used to lrerf it. It will be'seen yfromv thedescription ofthe method, and the opera-y mechanism adapted to extend adjacent aV relatively long coall face, and having both` vertical and lateral iexibility wherebyv it may be adjustedy to conformV to irregularities .inthe contour of the mine floor or `of they falce of the vein.

A further object is toprovide means to. si-

multaneously impart uniformv lateral motion.v

to alll parts ofa flexible cuttingfand conveying mechanism, such asv 1s 'above' mentioned,

tov maintain it in working .relation with the` coal face;

`A `further Objectis to pro'v'ide' means toautomatically adjust a mechanism'of the class described 'to conform tothe irregularities in the contour of the mine loor orof the face of the vein;

The means whereby `I attaintheselobjects larel'fully set fortlr in the following specilication, reference being had ,tol the accom? panying drawings, of whicht v Fig. I is a general Vplan view of-alongwall coal cutting mechanism embodying my present'invention. t I f l Fig. 2 is an end elevation of the mechanism` illustrated in Fig.` 1. f

' Fig. 3 is adetail, on anV enlarged scale, of the feeding devicesfillustrated in Fig. l; Y Fig. 4 is a' section taken along thel line IV-IV of Fig. A3.V i Fig. 5 is-a fragmentary view similar to 4, showing the adaptation of my improved coal cutting mechanism tothe transportation of the dislodged coal llongitudinally of theA coal face. i 'Y yFigsif 6,17, 8, 9" and 10 are-diagrammatic illustrations ofthe method of operating the machine.y f f 'FigJll is a view similar toV Fig. 2, showing means 'for effecting movement of the chain at different speeds.

- f Fig. l2 is a detail of the cutter cha-in showing itl equipped with a sweep or Hight for gathering the material. Y

cutterl i Fig. 13 is a view substantiallyon the line l lilof Fig. 12,looking in the direction' of the arrows.y i 1 Fig. lll'fis a detail perspective view of they pivotpin' for securing the sweep tothe'chain.

In referring tothe drawings, like nu"- merals indicate similar parts in the several; views.

' For purposes of illustration, I have shown in thedrawings an installation adapted "to the recovery of avery thin vein ofcoal. As here illustrated, the* numeral 1 indicates av panel ormass of coal'lyingbetween two parallel entries 2'and13. The panel l has avworling face l extending perpendicularlyto saidv entries, and the length of this face depends the-mine. Owingto the extreme thinness of Vuponthe geological conditions existing in coa-l'l to cut it.

the vein, it has been necessary to take up -material from the mine floor, thus depressing the bottom of the entry 2, as shown at 5 in Figs. 9 and 10, to afford suiiicient headroom for the convenient operation of the pit cars 6 by which dislodged coal is transported from the mine. A bench 7 is retainedV along one side of the entry for the convenient handling of the power devices associated with the mining mechanism, as will bek more fully hereinafter described. The roof 8, adjacent the working face, may be supported in any preferred manner, as by a row of timber posts 9 positioned in the rear of the mining mechanism, which, as the face 4 recedes, may, from time to time, bemoved towards the coal face to allow the subsidance of the overlying strata. As these matters'are well understood in the mining art, further description of them is not thought to berequired atthis time.V 1

Positioned adjacent the coal face 4 and extending along its entire length, is a frame 10, upon which the coal engaging mechanism is mounted For purposes of illustration, I have here shown an undercutting mechanism adapted to form a kerf extending entirely across the face of the vein, but it is to be understood that other mechanism adapted to perform other operations may be so mounted without departure from the spirit of my invention. The frame 10 is preferably composed of a plurality of cutter framesections 10a, 10b, 100, etc., ar-

ranged in longitudinal alignment, and each provided with a longitudinally extending lug 11 projecting into a recess of the adjacent section to which it is connected by a coupling pin 12. These p artsare so proportioned that `the Vadjacent sections are connected together with a measure of flexibility both vertically and horizontally. Formed on the lateral edges of the sections 10a, 10b, 100, etc. are guideways 13 in which travels the cutter chain 14 which is of the well known construction having laterally projecting renewable cutter bits 15 adapted to engage the The guideways 13 of these sections will preferably be flared at `their ends, both laterally and vertically, as indicated in dotted lines at 13a, Fig. 3, so that as jthe sections flex relative to one another, as indicated in Figs. 8 and 9, where the outermost section is shown 'an'gularly disposed with respect to the rest of the line, the cutterchain will travel smoothly past the adjacent ends of the sections 10a, 10b, 10c, etc. These cutter bits 15 also act to drag dislodged fragments of coal longitudinally of the coal face 4, and the last-section lOof the cutter frame projects beyond the edge of the bench 7 to discharge such loose material into a suitably positionedy pit car 6. An aprongl, of "any suitable material andV construction, may be placed betgveen theedge of the bench 7, and

Formed on the outer end of the section 10a of the cutter frame is an upwardly projecting hub 17 in which is journaled the vertical head shaft 18 to which is attached thehead sprocketwheel by which the cutter chain 14 is actuated in the manner well understood in the mining machine art. The hub 17 is rotatably mounted in a sleeve 19 formed on the rearward end of an arm 2O which is rigidly attached to the frame 21 of the power mechanism. The frame 21 rests directly upon the mine floor and is slidable thereon, 'and these parts are so proportioned that a clear space is provided beneath the arm 20 and between the cutter frame 1() and power frame 21 for the passage of loose material to the pit cars 6. Mounted upon the frame 21 is a motor by which the machine is actuated. This motor may be vof any preferred type adapted to the conditions under which. the machine is operated. For purposes of illustration, I have shown an electric motor 22 to the ar-mature shaft of ,which is attached a worm 23 which engages a suitable worm gear 24 fixed to the vertical shaft 25. The shaft 25 is journaled in suitable bearings of the power-frame, and at its upper end is fixed a sprocket wheel 26 which is connected bya suitable endless chain 27 with the sprocket wheel 28 fixed to the head shaft 18 to actuate the cutter chain 14. Mounted upon the power frame 21 is a winding drum 29 which is connected by suitable gearingwith the motor 22 and provided with suitable mechanism to control its actuation, for purposes which will hereinafter appear. As the arrangement of such gearing is well understood in the mining machine art, and as it forms no part in the'present invention, further description is not thought to be required at this time.

[In order that the machine may be properly manipulated relative to the coal, I have provided a feeding mechanism comprising a rope 30 windable upon the drum 29 of the power mechanism, and adapted to cooperate with a plurality of anchor jacks 31 positioned outside of the machine, to uniformly move the cutter frame 10 laterally towards and from thefcoal face. Fixed to each section 10a, 10b, 10c, etc. of the cutter frame, and projecting perpendicular thereto, is an arm 32 shaped adjacent the cutter frame to form a sliding shoe 33 which engages the mine floor to support the cutter frame 10. The cutter frame 10 will preferably, as best shown in Figs. 4 and 5, be mounted on the end-of the frame 32 adjacent the shoe 33 in an inclined position, so as to provide clearance for the. bits 15, the shoe 33 being chaneled, as shown, to receive the lower run of the bits. In this position of the cutter frame 10, it will be seen that the bits 15 at the rear of the frame will isf cut inIk a higher:planewthan-y the bits at the front end of the framelO- and form a clearance on: the rearside of the frame for themselvesl and@ forthe sheaves 42 andtheir'associated pants. At its outer'endithereis@ provided: a; vertically extending adjusting` screw 34 threaded infan apertureiofl the arm 32, and haNingat its upper'end-a handvwheel 35for. its convenient ma-nipulation.` At its lower endithe screw 34"V is provided with a floor engaging foot' 36 adapted; toV sliding contact with the` min-e floor. Bythe adjustment of the screw' 34 the arm 32 may be rocked about the sliding; shoe 33 to eifectv vertical adjustment. of the forward, or active,.side of the cutter1 frame. Extending; longitudinally of the .arm 32 is a slot 3T thro-ugh which, extends the anchor jack 31 which is of the well knownf construction having a part; 33 adapted to engage the mine floor,l and' a tubular part 39.r telescoping.

therewith and adapted to engage` they mine roof. The slot 37, as will be clear from a. consideration of Fig. 3, provides a passageway whichpermits forwardv and backwardi movement of thev arm 32v andthe cutterarms carried thereby, relative to the jack; 3l.v The: upper portion of the floor engaging part 38 is screw threaded,.and tothis part'isflitted a hand wheel nut 40 by the adjustment of which the tubular part; 39 mayk be forced against the mine rooff to securely clamp .the jack` in position.4 A guidesheave 411 journaled upon theoorengagingp'artsz38 of the anchor ack, ispositioned in substantially the same horizontalv plane'as other guide` sheaves 42 and 43` whichv are mounted' respectively at the inner andv outerends of the armA 32..

The-rope 30, after passing around:I suitable: guide sheaves 44, 45 and 46t ofthe power frame, is passed aroundv the sheavesf42 andf43 of each successive armi 32: and engages the- Y no.;

Gliy

sheave 41 of each successive anchorjack; 31:, as illustrated in Figs. 3,1and: 6. When now thewinding drum 29: is. actuated to wind thel rope 30,' the shortening of the bightsf 47'a`nd 58- at each anchor-jackwill-movethe cutter* frame forwardly to causefthecutter bts15 to engage the coalto-"cut it.. In order that' the; cutter bits ofthe return;` strandi of V the chain 13-may clear thefshoes33, the cutter fname 10 may be inclinedl; transversely of -its length. JHowever, the upperl bitsfoffthe re:- tunn. strand, as has .been stated, engage the` coalat theftop off` the kerf to; cutasufcient. clearance forl the passagegof the chain and: to clear a sufficient space for the convenient operation of thefed rope 30 and its guide shea-ves 42, asis clearly illustrated. inFigI.. 4-

of the-drawings. Aftenthe "cutterframe hash been advanced beneath thecoal -tothedesired depth, the rope30willbereadj usted about the sheaves/41 and 42, asi illustrated in Fig; 71,; by throwingl the draft-rope 30A offxthe sl eaves 43 and reversing the loop on, the;V anchorY sheave 41,. sothat. draf-t onthe rope; -30VV from the winding; drum'will: cause the cutterfra-me.

Jtobe-.move'd towardthe coal facev insuch. mannen that when.A the; kdrum` 29 is actuated, the cutter frame will,r be lmoved rearwardly and: withdrawnpfrom the kerf. .After the coal has been thus ,undercut thev coal above;

the kerf may bev broken dow-n in` any preferred manner, asby the use of explosives, the feed rope30 again adjusted aboutthe sheaves 42, 43; and 41, as illustrated: in Fig. 8,a'fter whichv actuation of the cutter chainwillv cause the: cutter bits 15 to'l engage thev dislodging fragments of coal: lying upon the mine floor and move themlongitudinally of theface 4-l over the apron 16-into thepit car 6; In order` that,.when the step of carrying out the coal,

conventionallyl illustrated: in Fig. 8 is beingy performed, the broken coalYmay be maur' tained, in` pro-per position to be engaged; by the carrying out strand of the cutter chain .and not {work :back over the rear off the fra-mes,-.I provide a suitable shield 49 having supporting lugs 50 adapted-,to engage apen-- SOI t-uresl of the cutter frame g` this shield may'L i be adjusted, as illustrated iny Fig. 5, to confine thedislodged coal to the forward side ofr the cutter frame.. i

In*y Figures 11 to 14, inclusive, I have shown my machine so: equipped as that' the cutterl chain may be driven at different speeds. It i'sdesirable to have thechain runfaster when it is cutting, than' when it isloading; out the construction` shownin FigureV 2, exceptk that;

ther sha-tts 1-8- and, 25 are extended, as shown in! Figuref1-1, and af relatively large sprocket.

52.1is. fixed onntl1e-shaft-18- Upon the eX- tended shaft 25a relatively small sprocket 53V is loosely f mounted, the sprockets 52 and:v 53 being connectedby a chain 54.1 The-sprocket invthisform-.of the invention will be loosely mounted on the shaft 25,*.instead of fixed thereto, as'inthe form shown in Figure-2, and, bothi the sprocket 53andthe'sprocket 55- are provided with clutch surfaces, so thateither one may loe-clutched tofthesha-ft,.any suitable clutch mechanism, 23 56, lbeing provided.

- -While eitherof the chain and sprocket de-A vices shown in Figure 1.1; maybe the` fast cutting drive, or the relatively slower. conveyingV drive, I have hereshown the upper sprockets 52.- and53as the sl'ow drive. The relatively small. sprocket: 53v will, fwhenthe clutch 56`l engagessit with the shaft, drive the sprocket 52andtheshafft 18-which operates the chain,

ata' slowerspeed,.so that thecutterbitswill not be swept through the material at suchiV IDD ` cutter chain Will be increased, so as to give an effective cutting speed.

^ Y It maybe desirable, in some circumstances, to relieve the long cutter chain of the Weight of a large number of bits, and this can be done by omitting alternate bits, or alternate groups of cutter bits, in sufficient number to avoid overloading the apparatus. It sometimes happens, With some grades of coal, that the cutter bits do not effectively bring out the material, and in such case I provide, as shown in Figures 12 and 13, a sweep or flight 57 Which may be attached to suitably formed links 58 of the chain. These fiights may be arranged alternately With-the-bits, or in any desired grouping. The flights 57 may, of course, take different forms, and the manner of attaching them to the links 58 may be varied. l have here shovvn a flat flight 57 at` tached to a projecting lug onthe link 58 by means ofa pin 59, andthat pin, as shown, is provided With a key 60 at one end designed to pass through key seats 61 in the lugs 62 of the flights 57, and the lug of the link 58. The pin 59 isalso preferably provided'at the endV opposite the key with an offset Weight, as63, so that When the pin is inserted, the Weight 63 will naturally fall to a pendant position, give a quarter turn to the pin, and bring the key 60 out of alignment With the key'seat 61, as shovvn in Figure 13.

From the foregoing, it will be seen that by this method, and by means of the apparatus for carrying out the method, the steps of cutting, breaking down, and carrying out the broken down coal may be very readily carried on with the single apparatus, by simply adaptingit to the different steps of the method. This eliminates the labor and timeincident to the use of one apparatus for cutting the coal, and another apparatus for transporting or carrying out the broken down coal.

' It vvill be seen also that the construction admits of adapting the cutter frame to various Widths of coal face, for, by constructing the cutter frame of the `assembled units, it

may be set up in different lengths by simply adding to or removing units, thus giving a construction' Which may be conveniently adapted' to panels of various Widths.

As has been pointed out, the cutterrfrafme is made upvof sections 10a, 10b, etc., flexibly connected, so that, as indicated in Figures 8 and 9, they can adjust themselves to contours other than perfectly horizontal or vertical ones. vFor example, in Figure'S, it will beobserved that the end unit lOf is out of alignment, and -closer to the Wall than the others, and in Figure 9 that same end frame has adapted itself to an irregular floor con-y tour.

.This frame construction admitsof differ` ent manipulations. of thev cutter bar. i It is possible to moveall of the cutter bar sec# tions simultaneously into. the coal, or the sections may be advanced into the coal in irregulary fashion, as shown in Figure 8.

This might be desirable, particularly in loading out broken down coal. By pushing in theend section, as, for example, the section 107C, Figure 8, the coal attheV bar end of the frame Will be picked up first, and then, as succeeding sections vWere pushed in, the coal Will be loaded out from the far end, gradually reducing the mass in length until it has been entirely removed.

y Other manipulations of the flexible frame, to meet particular conditions, are, of course, possible,'and prop'erly'within my invention.

l do not Wish to be restricted to the precise construction andarrangement of parts here disclosed, since, While the embodiment of my invention Which has been described and illustrated is primarily an undercutting mechanism adapted to be used in a secondary capacity as a conveyor,.it is apparent that other coal Working devices, such as conveyors of .various sorts, may be constructed so as .to fall Within the spirit of myinvention.

hat I claim is 1,111 a coal mining apparatus, the combination with an elongated frame adapted to rest upon and slide over the mine floor said frame comprising a plurality of longitudinally aligned flexibly connected sections, an endless chain adapted to travel in guideways extending longitudinally ofsaid frame, cutter bits projecting laterally from said chain and adapted to engage the coal to cut it, means to actuate the chain, and means to simultaneously apply laterall moving effort tok each of said sections as and for the purpose set forth. i

2. In a coal mining apparatus, the combination-With an elongated frame adapted to rest upon and slide vover the floor of the mine said frame comprising a plurality of longitudinally aligned flexibly connected sections, anv endless chain adapted totravel in guide- Waysv extendingl longitudinally of said frame, cutter bits projecting laterally, from said chain and adapted to engage the coal to `cut it, means to actuate the chain, and means actuated bythe chain actuating means to simultaneously apply lateral moving effort to each of said frame sections as and for the purpose set forth.- Q

3. In a coal mining apparatus, theY combination With an elongated frame adapted tol rest upon and slideover the floor of the mine, said frame comprising a plurality of longitudinally aligned yflexibly connected sections, an endless chain adapted to travel in 'guideways extending longitudinally of said frame, cutter bits projecting Alaterally fromV said chain and adapted to engage the nis Liseigaae coal ltocut it, a motor mounted =0n one of the sections 4of 4said frame connected Aand -arranged Y.to :actuate ysaid lcutter chain, and 'means actuated by 'said motor to simultanefously fapply lateral movi-ng eifort to 'eachfof :said frame sections as and vfor thefpurfpose set forth.

4. In la coa-l mining apparatus, Jthe -com- Ebination with .an lelongated frame adapted to rest upon and slide over the floor of the mine, said frame :comprising a plurality of longitudinally aligned flexibly 'connected sections, lan end-less flexible idraft device adapted to travel in .guideways extending longitudinally of said frame, material fengaging `elements carried by said draft device, .means to actuate said draft device, and means to simultaneously apply lateral'moving effort to each of said frame sections as .and for the purpose jset forth. i f- 5. In a coal mining apparatus, the combination with `an elongated frame adapted to .rest upon and slide over thefloor vo'f the mine, said frameconipri-sing a pluarlity of longitudinally aligned flexibly connected sections, an endless flexible 'draft v device .adapted to travel in guide'ways extending 4long gi-tudinally of said frame, material, engaging elements carried by said draft dev-ice, .power devices upon said frame to actuate said draft device, fand -mechanism actuated by said power devices adapted to simultaneously apply lateral moving elfort toeaclh of saidsections as and for the/purpose set forth. n

6. In a coal mining apparatus, 'the 4combin ation with an elongated frame adapted to rest 'upon and slide over the floor ofthe mine, said frame comprising a plurality oflongt tudina'lly aligned 'flexibly connected sections, of van endless flexible draft device adapted 'to travel in guideways yextending longitudinally of said trame, material engaging `elements carried 'by `said draft device, power devices :upon said frame to acu'ate said draft device, rope guiding devices upon each frame Vsection, 'an abutment Avexternal of said frame adjacent each frame section, a rope 'adapted to engage said guiding devices and said abut- 4ments, and means to tension `said rope to Asimultaneously Aapply lateralmoving effort to-each vof said frame sections as andy for the purpose set forth.

7. In a coalmining apparatus, the combination with an elongated :frame adapted to rest npon and slide over the floor of the mine, said frame comprising a plurality of longitudinally aligned flexibly connected sections, ra laterally projecting arm extending perpendicular to each section, an endless flexn -ible draft Evdev-ice adapted 'toftrave'l in guidef `ways extendingflongitudinally of said iframe, material engaging elements carried by said draft device, power devices-upon'said Aframe -to actuate said draft device, a plurality kof rope `lguiding @devices mounted :upon said laterally 'proiecting arms, an abutment-external Tof 'said vframe adjacent eachof said arms,

Ia lrope adapted -tofengage the lguiding devices npon'the farms yand the 'abutments, and means actuated by said power devices to tension said Iropeto simultaneously apply lateral moving effort to each of said frame sections 'as for the purpose set forth'.

8. in 'a coal mining apparatus, the com-` bination with anelongated frame adapted to rest upon and slide over'the floor yof the mine, `said 'frame comprising a plurality of 'longitudifnally aligned flexibly connected sections, s .Y

Aa later-ally projectingrarm'extending perpendicular Vrto eachsection, an endless flexible draiftY device adapted to travel in guideways extending longitudinally of `said frame, ma- ;terial engaging elements carried by said `draft device, aplurality of rope 4guiding de- `vices mounted upon `said 'laterally projectingrarms-,anfabutment external of said frame adiacent each of` said arms and engaging guidevsays thereof, a rope adapted to engage ,Y

framesec'tions as and forthe purpose set connected sections, a laterally projecting 4arm ,Y

extending perpendicular to each section, a 'shoe formed on each arm adapted to slidably ino engage the mine floor to support its frame f section, an endless flexible draft device 'adapted to travel in guideways extending if longitudinally of said frame, materialengaging 'elements carried by said `draft device, power devices upon said'frame to actuate said 'draft'devica and lmeans actuatedV ,by` said power devices and cooperating with said arms and -an abutment adjacent each arm to simultaneously "apply moving .effort to eac'h `of said frame sections as and-for the purpose se't forth.'y

10. In a coal mining apparatus, Ithe Iconibin'ation with an elongated frame comprising fa. plurality 4of lon gitudinally aligned flexibly Yconnected sections each Iof which is provided with a supporting shoe slidably enigagin'g the mine floor, longitudinally aligned i guideways in said 4frame sections wherein travels an endless flexible draft device, and means to rock said frame sections -upontheir .supporting shoesl .to `effect the alignment of said guideways as and for vthe purpose yset forth.

ll. In a coal mining apparatus, the combination with an elongated frame kcomprising Ia plurality of longitudinally aligned flexibly connected sections each of which is provid ed with a supporting shoe -slidably engaging the izo mine floor, longitudinally aligned guideways in said frame sections wherei'nrrtravels an endless flexible draft device, a laterally projecting arm extending perpendicularvto each section, and means to vertically adjust the remote ends of said arms to effect the alignment of said guideways as and for the purpose set forth.v l

12. In a coal mining apparatus, the combination with an elongated frame comprising a plurality of longitudinally aligned flexibly connected sections each of which is provided with a supporting shoe slidably engaging the mine floor, longitudinally aligned guideways in said Vframe sections wherein travels an endless flexible draft device, a laterally projecting arm extending perpendicular to each section, an adjusting screw threaded in an raperture of each arin and adapted to engage .the mine iioor,and means to adjust said screw relative to said arm to effect the alignment of said guideways as and for the purpose set forth. Y

13. In an apparatus of the class described, the combination with an endless flexibledraft device, of material engaging elements attached to said draft device, and a guiding and supporting frame adapted to cooperate with said draft device to cause the engagement of said elements with the material to be operated upon, said frame comprising a plurality of llongitudinally aligned flexibly connected `sections as and for the purpose set forth.

14. In an apparatus of theV class described, theA combinationv with an elongated frame composed of a plurality of longitudinally aligned flexibly connected sections, of means to simultaneously apply lateral moving effort to each of said sections as and for the purpose set forth.y

15." In an apparatus of the class described, the combination with an elongated frame composed of a plurality of longitudinally aligned flexibly connected sections, adapted to ilexure in either-of two intersectingV planes extending longitudinally of the frame, of means to simultaneously apply lateral moving effort to each of said sections as and for the purpose set forth.

16. In an apparatus of the class described, the combination of a cutter frame made up of a plurality of'flexibly connected sections,

a cutter chain carried by said flexible cutter frame, means for driving said chain,'and means for moving the units of said flexible frame toward'a coal face substantiallyat the `same time.

17 In an apparatus of the class described, the combination of a cutter frame made up a cutter chain carried by said cutter frame, means for driving said chain, and means associated with each unit of said flexible frame to move such units toward a, C0211 face sub,-

stantially at the same time.l j

18. In an apparatus of the class described, Athe combination of an elongated cutter frame, a cutter chain carried by said frame, means for driving said chain, a plurality of cable engaging devices extending rearwardly from said frame, and a cable engaging each of said devices to exert moving pressure upon the frame at a. plurality ofpoints throughout its length to advance or retract it relative to a coal face.

19. In an apparatus of the class described, the combination of an elongated cutter frame, a cutter chain carried thereby, means for .driving said chain, a plurality of cable engaging devices extending rearwardly from said frame, a continuous cable extending substantially parallel to said frame and having laterally disposed loops engaged with said cable engaging devices, and means for exerting draft on said cable to eff-ect movement of said frame toward or from a coal face.

20. In an apparatus of the class described, the combination of a cutter frame, a cutter chain carried thereby, means for driving said chain, rigidly disposed arms projecting rearwardly from said frame, cable engaging devices carried by said arms, a cable disposed substantially parallel to said frame and having loops extending laterally therefrom substantially in line with said arms, an anchor device for said loops, and means for exerting draft` upon said cable to effect movement of said cutter frame.

21.V In an-apparatus of the class described, the combination of a cutter frame, a chain carried thereby, means for Vdriving said chain, a plurality of arms extending from said frame and each having a longitudinally disposed slot, cable engaging devices carried by said arms, cable engaging anchors passing throughthe slots in said arms, a cable disposed substantially parallel to said frame having loops enga-ged'with said cable engaging devices and said anchors, and mea-ns for exerting, draft on said cable to move said frame. l 22. In an apparatus of the class described, a cutter frame formed of a plurality of sec- Ytions connected end to end for relative verti- Galand horizontal movement, a cutter carried by said frame,rarms extending rearwardly from each of said units, cable engaging devices on said arms, cable engaging anchors, a cable disposed substantially parallel to said frameand having loops engaged with said cableengaging devices and said anchors. and means for'ex'erting ydraft on said cable to move said frame. l

23. In an apparatus of the class described, an inclined cutter -frameformed of a plurality of sections connected end to end for relative vertical and horizontal movement, a cutter carried by said frame, arms extending rearwardlyvfrom each of said units, means for adjusting said arms vertically, cable entravel in guideways along the lateral edges of .said cutter frame to enga-ge the coal to cut a kerf therein, and means for tilting said supports'to so incline the cutter'frame'that'the cutter chain on opposite sides of `said frame shall travel in different horizontal planesV as and for the purpose set forth.

25. In an apparatus of the'class described, the combination with anV elongated frame comprising a plurality `of aligned flexibly connected sections, an endless-chain adapted to travel in guideways formed in said 4frame sections, material engaging elements carried by said endless krchain, means to drive said chain, and means to move the units of vsaid flexible frame towards the material which is lto be moved.

26.' In an apparatus ofthe class described, the combination with a cutter framesupport adapted to rest upon and slide over the floor of a mine, cutting mechanism carried by said frame adapted to engage the coal to form a lrerf therein, cutting mechanism inthe rear of the first mentioned cutting mechanism adapted to engage the coal abovesaid lrerf to widen said lrerf, means to move said support to cause said cutting mechanism to engage the coa-l to cut it,iand means to roclrsaid cutting mechanisms about a substantially constant axis intermediate Vtheir paths. n f f 27. In an apparatus of the class described, the combination of a cutter frame consisting of a plurality of ilexibly' connected sections, a cutter chain carried by saidflexible cutter frame, and means for tilting each section of the frame independently of the others.

28. In an apparatus of the class described, the combination of a frame consisting of a plurality of flexibly connected sections, an endless draft element mounted upon said frames, material engaging elements carried by said draft element, and means for tilting each section transversely of its longitudinal axis.

29. In an apparatus of the class described, the combination of a frame consisting of a plurality of flexibly connected sections, an endless draft element mounted upon said frames, material engaging elements carried by said draft element, and screw means car ried by each section for tilting each section transversely of its longitudinal axis.

30.` Inanfapparatus of the vclass described, the combination ofI a frame consisting of a plurality of flexibly connected sections, an endless flexible draft device carried yby said sections, material engaging elements carried 2j by ysaid :draft device, each section having a laterally projecting arm, and means on the end of said arm for tilting each section.-

i 3l. In' an apparatus of the class described, fthe combination of a cutter frame Vadapted 5.55 to be yarranged in a position inclined transversely of its longitudinal dimension, feeding means rfor moving said vframe transversely, and a cutter chain mounted ton said inclined frame with its cutter `bits on opposite sides vof the frame lying in different fhorizontal planes to cut a clearance for said feeding means. I

32. In an apparatus of the class described, the vcombination'of a plurality of frames Ggf, adapted to be assembled in an extended series, .an endless flexible draft device mounted upon said frames, material engaging elements carried by said draft-device, and means for connecting said'frames together to permit relative angular movement thereof.

33. In an apparatus of the class described, the combination of a plurality of frames `adapted to 'be assembled in an extended series, anendless flexible draft device mounted upon @$5 said frames, materialengaging elements carried by said draft device-and means for connecting said frames together to permit flexure thereof in either of two intersecting planes.

34. In an apparatus of the class described,i00 Ythe 'combination with .a plurality of sections adaptedtobe assembled in an extended series, the adjacent ends of adjacent sections being flexibly connected by a 'projectionof one entering` `the recess of the other. and an endless F105 flexible draft device mounted upon said sections.

f 35. In a machine of the class described, an elongated base member composed of artic- `ulated sections, material-engaging elements-'no movable throughout said sections longitudi- `nally'thereof, said sections being movable in a lateral direction toV conform to the outlines cfa-mass of material and 4to Aengage said elements therewith. qu

36.' In a machineoi` the class described, an elongated base member composed of articulated sections, an endless draft'device traversable along said sections, material-engaging elements on said draft device, said sections'go Vbeing movable in a lateral direction to conform to" the outlines of 4a mass of kmaterial and to engage said elements therewith.

37. In a machine of the class described, an elongated ybase member composedof articulated sections, material-engaging elements movable 'throughout said sections longitud-inally thereof, and means to apply lateral inoviiigforce `to la selected section to engage respectiveelements with a mass' of materialf1130 38. In a machine of the class described, an elongated base member composed of articulated sections, material-engaging elements movable throughout said sections longitudinally thereof, and means to apply Alateral moving force to selected'sections to engage respective elements with a mass of material.

39. In a machine of the class described, an elongated base member composed of articulated sections, material-engaging elements movable throughout said sections longitudi- Vconsisting in alternately advancing a keriing instrumentality into a mine face and withdrawing it therefrom, each advance movement subsequent to a withdrawal being substantially twice the distance of the withdrawal movement, the coal being broken down prior to such subsequent advance movement, and said instrumentality in its advance removing the broken down material and then underkering the succeeding increment.

42. The method of taking coal from an extended mine face between two-workings consisting in alternately advancing a kerfing instrumentality into the mine face throughout its length and withdrawing it therefrom, each advance movement subsequent to a withdrawal being substantially twice the distance of the withdrawal movement, the coal being broken down prior to such subsequent advance movement, and said instrumentality in its advance removing the broken down material and then under-kerfing the succeeding increment.

' L3-In an appartus of the class described, the combination with a cutter frame support adapted to rest upon and slide over the floor of a mine, an elongated cutter frame mounted thereon and movable laterally therewith towards an extended coal face, a cutter chain adapted to travel in guideways formed on the lateral edges of said cutter frame and adapted to engage the coal to form a kerf therein, said cutter frame being so inclined that the cutter chain on opposite sides of said frame shall travel in different horizontal planes to cut a lerf of suiiicient width to permit the free entrance of the frame support therein.

vt-l. In an apparatus of the class described, the combination with a-cutter frame support Vchain on opposite sides thereof shall travel inv different horizontal planes to out a lrerf of sufficient width to permit the free entrance of the frame support therein, the central horizontal plane of the kerf remaining substantially constant at various inclinations of said frame.

45. In an apparatus of the class described, the combinationwith a plurality of cutter Aframe supports adapted to rest upon and slide over the floor of a mine, an elongated cutter frame. mounted on said supports and movable laterally therewith towards an extended coal face, a cutter chain adapted to travel in guideways formed on the ylateral edges of said cutter frame and adapted to engage the coal to form a kerf therein, and means for tilting said supports to V.tilt said cutter frame about an axis substantially adjacent the longitudinal axis of the frame that the cutter chain on opposite sides thereof shall travel in different horizontal planes to cut a lerf of suicient width to permit the free entrance of the frame support therein.

46. In an appartus Yof the class described, the combination with a plurality of cutter frame supports adapted to rest upon and slide over the iioor of the mine, an elongated cutter frame mounted upon said supports and movable laterally therewith perpendicularly towards the coal face, a cutter chain adapted to travel in guideways along the lateral edges of said cutter frame to engage the coal to cut a lrerf therein, said frame being so inclined to the horizontal that the cutter chain on opposite sides of said frame shall travel in different horizontal planes to cut a kerf of sufficient widthto permit the free entrance of the frame support therein.

In testimony whereof Ihave hereunto set my hand.

NILS D. LEVIN. 

